SS9901-CS040727 (2)From:
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Date:
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"Cooper, Erika" <erika.cooper@tcb.aecom.com>
<kgriffin@ci.coppell.tx.us>
7/27/2004 4:26:48 PM
HDPE Piping - mandrel use
Per our conversation this morning, I have talked to several people
regarding the use of mandrels for verifying proper installation of HDPE
pipe. While mandrels can and have been used, inspection by television
camera is the preferred method of the pipe manufacturers if inspection
is necessary. If mandrels are to be used, the design of the mandrel
must take into account the allowable pipe wall thickness variations and
inside diameter, the inner bead at joints, and allowable deflection. As
you mentioned this morning, the major concern with using a mandrel is
the potential for lodging the mandrel inside the pipe, resulting in
costly and disruptive efforts to dig the mandrel out.
The main drawback to television inspection (from the Contractor's
perspective) is that the water in the line would need to be flushed
prior to televising the line. However, it seems that this may be the
best course of action under the circumstances.
Please let me know if we can provide any additional information.
Thanks,
Erika
Erika Cooper, P.E.
Turner Collie & Braden, Inc.
17300 Dallas Parkway - Suite 1010
Dallas, Texas 75248-1145
972-735-3000
Fax 972-735-3001
Direct 972~735-3056
Email erika.cooper@tcb.aecom.com